Systems and methods for cable and wlan coexistence

ABSTRACT

Various of the disclosed embodiments improve the operations of a combined access point/Cable modem. Though the access point component and the Cable modem component may perform operations in different spectrums, harmonics in the Cable spectrum may interfere with operations, e.g., in the 2.4 GHz and 5 GHz range, of the access point. Some embodiments implement a remediation and/or channel transition process for the access point following detection of Cable-related interference. During remediation, the device may, e.g., adjust the wireless power levels, EDCA backoff times, signal thresholds, etc. In some embodiments, if the remediation actions prove ineffective, the wireless peers may be relocated to a channel further from the interfering Cable harmonics. The determination to remediate or reallocate may be based on various contextual factors, e.g., the character of the peer devices and the applications being run.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. patent application Ser. No.14/572,007, filed Dec. 16, 2014, which application is incorporatedherein in its entirety by this reference thereto.

TECHNICAL FIELD

The disclosed embodiments relate to systems and methods forcommunication coexistence.

BACKGROUND

Many users would prefer that their network devices be versatile andcompact in their functionality. Thus, Cable modems are often providedwith Cable interface connections, but also with local wireless access,e.g., via a WLAN Access Point. In this manner, the user may receiveInternet access, television, and other services along their Cableconnection. They can place the single Cable modem at one location intheir home or office and interface their remaining wireless and Cabledevices through the single, compact interface.

Unfortunately, the dual presence of Cable and WLAN devices in a singledevice can result in suboptimal wireless performance. Cable signalspresent either within the Cable modem or in wires leading to/from themodem can operate at frequencies having harmonics that may degradewireless performance. Thus, users are often forced to purchase aseparate access point which they connect with the Cable modem at alocation with less interference. The Cable modem is consequently lessversatile and fails to provide the unified functionality the userdesired. Such redundant purchasing of wireless capability by the useroften diminishes the user's valuation of the dual wireless modem.

BRIEF DESCRIPTION OF THE DRAWINGS

The techniques introduced here may be better understood by referring tothe following Detailed Description in conjunction with the accompanyingdrawings, in which like reference numerals indicate identical orfunctionally similar elements:

FIG. 1 is a block diagram illustrating an example instance of Cable andwireless interference as may occur in some embodiments;

FIG. 2 is a block diagram illustrating the channel topology as may applyin some embodiments;

FIG. 3 is a table of the harmonically related carriers (HRC) Cable modemtermination system (CMTS) Interference to 2.4 G Radio experienced duringexperimentation;

FIG. 4 is a table of the Standard (STD) CMTS Interference to 2.4 G Radioexperienced during experimentation;

FIG. 5 is a table of the Cable Interference experienced at a 5 G Radioduring experimentation;

FIG. 6 is a table of the Cable Interference experienced at a 5 G Radioduring experimentation;

FIG. 7 is a plot of the Cable Interference experienced at a WNDR3800Radio during experimentation;

FIG. 8 is a block diagram illustrating possible corrective topologiesapplied in some embodiments;

FIG. 9 is a flow diagram illustrating an adaptation process as may beimplemented in some embodiments;

FIG. 10 is a block diagram illustrating a cascaded weight-based factorassessment for generating a remediation and channel transition metric asmay be implemented in some embodiments;

FIG. 11 is a block diagram illustrating an example channel reassignmentas may occur in some embodiments; and

FIG. 12 is a block diagram of a computer system as may be used toimplement features of some of the embodiments.

While the flow and sequence diagrams presented herein show anorganization designed to make them more comprehensible by a humanreader, those skilled in the art will appreciate that actual datastructures used to store this information may differ from what is shown,in that they, for example, may be organized in a different manner; maycontain more or less information than shown; may be compressed and/orencrypted; etc.

The headings provided herein are for convenience only and do notnecessarily affect the scope or meaning of the claimed embodiments.Further, the drawings have not necessarily been drawn to scale. Forexample, the dimensions of some of the elements in the figures may beexpanded or reduced to help improve the understanding of theembodiments. Similarly, some components and/or operations may beseparated into different blocks or combined into a single block for thepurposes of discussion of some of the embodiments. Moreover, while thevarious embodiments are amenable to various modifications andalternative forms, specific embodiments have been shown by way ofexample in the drawings and are described in detail below. Theintention, however, is not to limit the particular embodimentsdescribed. On the contrary, the embodiments are intended to cover allmodifications, equivalents, and alternatives falling within the scope ofthe disclosed embodiments as defined by the appended claims.

DETAILED DESCRIPTION

Various of the disclosed embodiments improve the operations of acombined Access Point (AP)/Cable modem. Though the AP component and theCable modem component may perform operations in different spectrums,harmonics in the Cable spectrum may interfere with operations, e.g., inthe 2.4 GHz and 5 GHz range, of the access point. Some embodimentsimplement a remediation and/or channel transition process for the accesspoint following detection of Cable-related interference. Duringremediation, the device may, e.g., adjust the wireless power levels,EDCA backoff times, signal thresholds, etc. In some embodiments, if theremediation actions prove ineffective, the wireless peers may berelocated to a channel further from the interfering Cable harmonics. Thedetermination to remediate or reallocate may be based on variouscontextual factors, e.g., the character of the peer devices, theavailable bandwidth, and the applications being run.

Various examples of the disclosed techniques will now be described infurther detail. The following description provides specific details fora thorough understanding and enabling description of these examples. Oneskilled in the relevant art will understand, however, that thetechniques discussed herein may be practiced without many of thesedetails. Likewise, one skilled in the relevant art will also understandthat the techniques can include many other obvious features notdescribed in detail herein. Additionally, some well-known structures orfunctions may not be shown or described in detail below, so as to avoidunnecessarily obscuring the relevant description.

The terminology used below is to be interpreted in its broadestreasonable manner, even though it is being used in conjunction with adetailed description of certain specific examples of the embodiments.Indeed, certain terms may even be emphasized below; however, anyterminology intended to be interpreted in any restricted manner will beovertly and specifically defined as such in this section.

Overview—Example Use Case

A wireless LAN AP operating in 2.4 GHz or 5 GHz may experience in-bandinterference as a result of harmonics or internodes from a Cable modemwhen operating in close proximity (e.g., as a single device). FIG. 1 isa block diagram illustrating an example instance of Cable and wirelessinterference at a dual Cable modem/access point 105 as may occur in someembodiments. The dual Cable modem/access point 105 may include awireless connection module 105 a (e.g., a WLAN Access Point) and a Cableconnection module 105 b (e.g., a Cable interface). The Cable connectionmodule 105 b may provide data connection, television and other servicesto various local devices 130 across a connection 115 which may be wiredor wireless. The wireless connection module 105 a may provide wirelessservices across connection 110 to devices 125 a, 125 b, e.g., wirelessconnection module 105 a may serve as an AP in a WiFi™ network 120. Thewireless services may include, e.g. Internet access, the creation of alocal infrastructure, and/or peer-to-peer management.

A Cable provider 110 may provide services to the dual Cable modem/accesspoint 105 across a network 150. Both a local connection 135 carryingCable data, Cable connections emanating from the device 105, and theoperations of the Cable connection module 105 b may generateinterferences 145 a, 145 b, 145 c. The Cable connection module 105 b maysupport different versions of the Data Over Cable Service InterfaceSpecification (DOCSIS) including DOCSIS 1.0, 1.1, 2.0, 3.0, 3.1 orfuture versions, or others standards, for example standards that supportNTSC channel operation, using standard (STD), Harmonic Related Carrier(HRC), or Incremental Related Carrier (IRC) frequency plans conformingto EIA-S542. Each of these signals may generate harmonics having aneffect on the WLAN operation. The WLAN component 105 a may not be awareof which features are provided via the Cable connection and so may needto infer the existence of interfering harmonics. In some embodiments,however, the Cable connection module 105 b may inform the wirelessconnection module 105 a of the operations being performed and thewireless connection module 105 a may identify the interfering harmonicsthat may result.

Data on the Cable channels may travel both up and downstream. Upstreamdata may travel, e.g. between the 5 to 42 MHz frequencies. In someembodiments, the Cable device may be designed to provide downstream dataflows as high as 1 GHz, 1.2 GHz, or 1.7 GH. Upstream data flow may be ashigh as 85 MHz, 200 MHz, or 400 MHz. FIG. 2 is a block diagramillustrating the channel topology as may apply in some embodiments. Asdepicted in FIG.2 the Cable device may be designed to provide downstreamdata flows 210 generally between 50 MHz to as high as 860 MHz whileupstream communications 205 may operate at less than 50 MHz. Channelspacing in North America is 6 MHz. Due to interference from Cablefrequency harmonics and internodes, the wireless connection module 105 amay transmit less or stop transmitting. The interference may raise theenergy levels in the wireless spectrum such that a WLAN AP will nottransmit or a WLAN receiver will be unable to receive a clear signal.This may result in lost packets and in in the receiver's sensitivity tothe desired signal range degrading over time (an effect referred to as“desensing”).

To mitigate this behavior, various embodiments contemplate having thewireless connection module 105 a manage the network, possibly avoidingthe use of channels experiencing considerable degradation, or otherwisemodifying its behavior in a triage-like pattern.

Cable Modem Channel Recognition

If the wireless connection module 105 a knows which channels the Cablemodel uses for uplink and downlink, it may take actions to avoid thepotential harmonics, or to mitigate the effect of the harmonics, fromthe downlink or uplink Cable signal. If the WLAN AP and Cable modem areintegrated into the same unit, the wireless LAN software may query theCable modem directly, to determine the Cable channel. Conversely, ifCable modem and AP are two separate units, then a communication circuitin the wireless connection module 105 a may automatically anticipate theharmonic interference (e.g., via preliminary channel energymeasurements). In some embodiments, an Ethernet connection between theCable modem and wireless LAN AP, e.g., may signal Cable activity usingan Ethernet connection. Standard APIs may be defined for a WLAN AP and acable modem which are connected to each other using Ethernet or anotherconnection, such that the WLAN AP or router can query the channel of thecable modem and use this information for channel selection

Upon determining the Cable model channels in operation, the wirelessconnection module 105 a may avoid using WLAN channels with potentialharmonics corresponding to the Cable model channels. For example, thewireless connection module 105 a may check for harmonic interference andif the harmonics' energy is above a predefined threshold, the wirelessconnection module 105 a may elect another channel for communication withits wireless peers.

2.4 G Harmonics

In some embodiments, for frequencies at or near 2.4 GHz the system mayfirst monitor the following harmonics arising from the downstream Cablechannel to verify that they are not encumbered by interference: 4thharmonics of channels between 601 MHz to 623 MHz and 3rd harmonics ofchannels between 800 MHz to 831 MHz. Other harmonics resulting fromdownstream or upstream Cable communications may be checked as well. Ifthe harmonics power is above a threshold the channels may be avoided.These determinations may be performed upon startup of the system and/orperiodically thereafter. Alternatively the WLAN receiver may measure thedegradation resulting from the major harmonics by switching to thosechannels and deciding if the channels are usable. Similar operations maybe performed in the 5 G range in some embodiments.

Experimental Results

FIG. 3 is a table of the HRC CMTS Interference experienced at a 2.4 GHzradio during experimentation. As illustrated, two of the HRC CMTSdownlink channels were determined to create 4th harmonics 1305interfering with channels 9-14 1310 of 2.4 GHz Wi-Fi operation. In someembodiments, the Access Point will select the cleanest channel (e.g.,with the lowest signal energy attributable to interference) that doesnot overlap with the harmonics signal. FIG. 4 is a table of the STD CMTSInterference for a 2.4 G Radio experienced during experimentation. Twoof the STD CMTS downlink channels 405 create interference for thechannels 410 of the 2.4 GHz band. FIG. 5 is a table of the CableInterference experienced at a 5 G Radio during experimentation. Channels510 were all affected by 8th and 9th harmonics 505 of the downstreamsignal. FIG. 6 is a table of the Cable Interference experienced at a 5 GRadio during experimentation. Channels 610 were affected by 8th and 9thharmonics 605 of the downstream signal. FIG. 7 is a plot of the CableInterference experienced at a WNDR3800 Radio during experimentation.

Experiments were also performed with a WNDR3800 wireless router providedby NETGEAR®. When a Cable Modem uses a frequency between 613.75 MHz to657 MHz for video signals, 4th Harmonics were identified within the 2.4GHz band higher channels. In the 2.4 GHz range, Channels 8 through 14were also affected by 600 MHz 4th Harmonics interference.

Various embodiments consider modem systems which anticipate interferencein the channels indicated above. For example, the systems maypreferentially scan these channels for interference energy levels priorto selecting them, or neighboring frequencies, for WLAN communication.

Corrective Action

FIG. 8 is a block diagram illustrating possible corrective topologiesapplied in some embodiments. In a dual Cable modem/access point 805containing both a WLAN component 810 and Cable connection component 820in close proximity, remediation logic 815 may be applied to manageoperations at each of the components 810 and 820. The remediation logic815 may indicate suitable channels to the WLAN component 810 based uponthe operations at the connection component 820. Some of these operationsare reflected in FIG. 9.

Alternatively, in some embodiments the Cable modem 855 containing aCable connection module 850 may be placed at least 36 inches 845 awayfrom the WLAN device 835 (e.g., a WNDR3800 wireless router) havingwireless connection module 840 to mitigate interference.

Adaptation Process

FIG. 9 is a flow diagram illustrating an adaptation process 900 as maybe implemented in some embodiments. The process 900 may be run, e.g., byremediation logic 815 on a dual Cable modem/access point 805. At block905 the system may determine what Cable operations are active at a Cabledevice, e.g., Cable connection module 820. At block 910, the system maydetermine the harmonics corresponding to the operations (e.g., theharmonics identified in FIGS. 3-6). For example, if the Cable modemcomponent has identified the channels or operations it is using to thesystem, the system may identify the relevant resultant harmonics in alook-up table.

At block 915, the system may determine if all the relevant harmonicshave been considered. If so, the system may sleep at block 920 or waituntil an event triggers (e.g., the usage of a new wireless channel, asignal from the cable connection module, etc.) the reassessment ofpossible Cable-related interference. For example, the Cable connectionmodule 850 may inform the logic when a new operation is being performed.This “event” may trigger a reassessment. Similarly, operations at theWLAN side, such as the addition of a new client device to a group, or arequest to transition to a new channel may constitute events triggeringa reassessment.

The buildup of software queues and hardware queues in the WLAN modulemay also be a trigger for reevaluating the situation. The number ofbeacons transmitted in a second is another trigger which may be takeninto account. On most APs, ten beacons per second are transmitted perSSID. If the AP can not access the channel to send the expected numberof beacons, e.g. ten beacons, this may be an indication that there iscable or other types of interference and, as a result, the number oftransmitted beacons may be used as a trigger.

Where harmonics remain for consideration, at block 925, the system mayconsider the next relevant harmonic. During a detection period at block930, the system may determine whether the energy levels attributable toa Cable operation harmonic exceed a given threshold in a wirelesschannel. The threshold may be both of time and energy, to reflect thatthe interference is a consistent phenomenon. In this manner, transitoryinterference may not result in a decision to avoid a channel associatedwith the harmonic. In some embodiments, the counters from WLAN physicallayer and MAC layer may be used to measure the severity and influence ofinterference. If the WLAN PHY module misdetects a packet preamble oninterference more than X per second, then this could be used as anindication that there is excessive interference.

If the MAC level counters show that the medium is busy more than Ypercent of the time that the WLAN module is not transmitting orreceiving WLAN packets, then this is an indication that there may beinterference from the WLAN module. To elaborate, WLAN layer 2 canmeasure the percentage of the time where there is WLAN activity. Whenthere is no WLAN activity, if there is no non-WLAN interference themedium is available for usage; but if there is non-WLAN interference,such as cable harmonic interference above an energy detection threshold,the medium may not be used. Therefore, the duration of the time whenthere is non-WLAN interference which results in backing off can be usedas a measure of the severity of interference.

Blocks 935-960 reflect various remediation steps which may mitigate theadverse effect of the interference. At block 935, the system maydetermine whether the interference power exceeds a second thresholdand/or the MAC and PHY parameter pass a second threshold. The secondthreshold may be designed to determine if filtering adjustments maysuffice to avoid the interference. If so, at block 940 the system mayadjust a signal reception threshold and/or filter and may request thesame or similar adjustment at a peer device. At block 945, the systemmay determine whether adjustment to the EDCA backoff parameters, energydetect threshold, packet detection threshold, or other thresholds maysuffice to mitigate the effects of the harmonic interference. If suchadjustments are expected to mitigate the interference, at block 950, thesystem may adjust the backoff interval or other parameters. At block955, the system may determine if a receiving antenna or a transmittingantenna power level may be adjusted to overcome the interference. Atblock 960, for example, the system may direct a peer device to increaseboth its transmission and reception power commensurately with changes atits own.

At block 965, the system may reassess the channel quality following oneor more of the remediation steps as well as consider the consequences ofany future planned remediation. If remediation has failed to achieve thedesired improvements, future remediation will prove unacceptablydetrimental, and/or a suitable alternative channel is available, than atblock 970, the system may perform a channel reallocation, moving one ormore client devices to a new channel with less interference (e.g., achannel identified in FIGS. 3-6 not expected to encounter harmoniceffects).

FIG. 10 is a block diagram illustrating an example cascaded weight-basedfactor assessment for generating a remediation 1015 and channeltransition metrics 1030 as may be implemented in some embodiments. Asindicated, a remediation metric 1015 may be generated as a weighted sumof various remediation factors, such as an anticipated power adjustment1005 a, EDCA backoff 1005 b, TX/RX power adjustment 1005 c, etc. Thesefactors may reflect the planned adjustments in the next iteration ofremediation if the coexistence continues to mitigate desired levels ofcommunication. These factors may be normalized by their correspondingweights 1010 a, 1010 b, 1010 c so that their effects on communicationmay be assessed. Thus, the remediation metric 1015 may be used todetermine whether additional, future remediation is suitable given thecurrent impact on channel quality.

A channel transition metric 1030 may also be generated by taking aweighted sum of the remediation metric 1015 with other channel conditionfactors, e.g., the quality of alternative channels 1020 b, thedifference between the desired bandwidth for applications and that whichis presently possible with the coexistence 1020 a, etc. with variousscaling factors 1025 a, 1025 b, 1025 c. The system may elect to initiatea channel transition based upon the channel transition metric's relationto a threshold. Though depicted as sums of weighted values in thisexample, one will recognize that business rules may also determinewhether remediation is performed or channel transitions are made.

Channel Reallocation

Various embodiments consider extending channel switch announcementbetween bands so that users can be moved, e.g., from 2.4 G to 5 GHzchannels or other bands which experience less coexistencecomplications—in this manner following a coexistence interferencedetermination as discussed herein appropriate corrective action may betaken. The specification may be modified, e.g., by extending channelannouncement messages such that they can be addressed by only one clientor a subset of clients, instead of moving all clients connected with anaccess point. Based on the percentage of time that interference isactive, the power of the interfering signal, and the traffic requirementof the Wi-Fi clients that are associated to the AP, the AP decides whichclients can stay in the band that has interference and which clientsneed to be moved to other bands. The AP sends a packet to direct theclients that need to be moved away to the band they need to be moved to.Various embodiments contemplate a combination of smart channel selectionof Wi-Fi access points (APs), transmit power control on APs and/or atclient devices, messaging between AP and clients for Wi-Fi powercontrol, smart receiver adjustment on Wi-Fi, and adding signaling suchthat traffic can be offloaded to Wi-Fi when possible.

The channel switch announcement element which is defined in section8.4.2.18 in IEEE 802.11REVmb document may be modified to optionally addclient MAC addressed or client association ID (AID)s for clients whichneed to be moved from one band on an AP to another band on the same AP.For example clients that need to move from 2.4 G radio to 5 G radio.Alternatively a new switch announcement element may be defined which isspecifically targeted to moving clients from one radio on an AP toanother radio. The switch announcement which could be used for APs thathave two radios on two bands, three radios on three bands, or more. Thechannel switch announcement may be done by adding the announcementelement to a beacon, it can be done by sending an action frame to eachclient that need to be moved, or it can be done using sending amulticast or broadcast packets to several clients that need to be moved.

The channel switch is done in a way to have seamless switch andminimized any disconnect time. This is done by giving client sometimebefore switching the channel and also by taking into account what typeof traffic the client is having when the decision is made to switch. Forexample if client is receiving a VoIP call and the call can bemaintained on the current channel, the switch may be postponed until theVoIP call is done. But if the client is doing a file transfer the switchcan be performed without the client noticing. If the client is having aVoIP call and switch is necessary, the switch may be tried the best timepossible for example, the switch may be done in the silence period ofthe call when nobody is talking.

FIG. 11 is a block diagram illustrating an example channel reassignmentas may occur in some embodiments. Initially a plurality of wirelessdevices 310 a, 310 b, 310 c may be in communication with an access point330 on a 2.4 GHz channel 305 a of an ISM band 325. Interference 315 froma neighboring band 320 may cause these communications to increasinglydegrade. Access point 330 and/or devices 310 a, 310 b, 310 c may detectthis interference and propose a channel transition away from the band320.

The AP 330 and devices 310 a, 310 b, 310 c may collectively orunilaterally decided to transition 335 to a new band. In this example,some of the devices (devices 310 b, 310 c) have elected to communicatewith the AP 330 on a 5 GHz channel 305 b. In some embodiments, the AP330 may detect the interfering activity and select a channel that isspaced further from the source of interference. For example, a higherpart of 2.4 G band may be chosen when band 40 detected. Devices 310 a,310 b, 310 c may send feedback to an AP about interfering activitytriggering WLAN channel change. The AP may retain at least one device(e.g., device 310 a) on the channel to determine if the coexistenceissues decrease over time. If the coexistence interference stabilizes atan acceptable level the devices may be returned to their originalconfiguration.

However, if all APs and devices in a region engage in this behavior itmay simply result in more WLAN APs and/or their devices clustering ontothe same channels. This may further reduce WLAN performance. To have aseamless channel switch at the AP, it may be preferable for clients tosupport Channel Switch Announcements (CSA) as defined in IEEE 802.11h orthe modified version of channel disclosed herein. However, some clientsmay not support our proposed CSA in 2.4 G band. To facilitate thedynamic change of channel, the regulatory bodies and Wi-Fi Alliance(WFA) (or a proprietary protocol among devices) may mandate the channelswitch announcement (CSA) support, on WLAN APs and clients. The standardmay also be modified to move the signal away from the 2.4 GHz WLAN bandwhen possible to mitigate interference. Accordingly, various embodimentstemper and complement channel transitions using other factors discussedherein. However, modification of the standards may not be pragmaticgiven the diversity if interests in the industry, and so variousembodiments instead implement a factor-based triage-like determinationof how best to handle coexistence artifacts.

Extending Channel Switch Protocols

Some embodiments propose the use of an extended channel switchannouncement element and/or extended channel switch announcement used inbeacon and other frames to cover switches between two different bands(example 2.4 GHz and 5 GHz, 2.4 GHz and sub1 G, 5 GHz and 60 GHz).

A Channel Switch Announcement frame which uses the Action frame may beextended to cover switching between different bands as discussed above.A channel switch mechanism may be targeted to a single client or groupof clients. The client MAC Address or AID may be used to specify theclients in a beacon or action frame.

In some embodiments, if the AP recognizes that the software or hardwarequeues are building up for a client, or sees that a delay requirement isnot being satisfied for a client, the AP may make the decision to movethe client from one band to another band.

In some embodiments, the AP may perform deep packet inspection (DPI) todetermine the type of traffic. Based on the DPI results for each clientpacket, the AP may decide which client to keep on each band and whichclient to move. For example, the AP may recognize a large file downloadvia DPI when the band is busy and subject to LTE interference. The APmay decide to move the download to another band as a download is nottiming critical requires considerable bandwidth. Conversely, the AP mayrecognize via DPI that a person is playing an interactive run and shootgame which does not require much bandwidth, but does require minimaldelay. Since an increase in delay may not be tolerated, the AP maydecide to keep the client on the same channel for the time being.

WLAN Channel switching

If all the receiver and transmitter mitigations fail to bring the linkquality up to any of the associated clients, the AP may choose to changethe channel of the radio which is facing the coexistence issue. When thechannel change happens, the AP takes into account the LTE coexistencewhen it picks the new channels. The AP may ask other clients forfeedback on LTE interference on all channels on the bands upon which theradios operated before it issues the channel switch. The LTEinterference feedback may be used in addition to the other statisticthat the AP collects to pick the best channel.

Computer System

FIG. 12 is a block diagram of a computer system as may be used toimplement features of some of the embodiments. The computing system 1100may include one or more central processing units (“processors”) 1105,memory 1110, input/output devices 1125 (e.g., keyboard and pointingdevices, display devices), storage devices 1120 (e.g., disk drives), andnetwork adapters 1130 (e.g., network interfaces) that are connected toan interconnect 1115. The interconnect 1115 is illustrated as anabstraction that represents any one or more separate physical buses,point to point connections, or both connected by appropriate bridges,adapters, or controllers. The interconnect 1115, therefore, may include,for example, a system bus, a Peripheral Component Interconnect (PCI) busor PCI-Express bus, a HyperTransport or industry standard architecture(ISA) bus, a small computer system interface (SCSI) bus, a universalserial bus (USB), IIC (I2C) bus, or an Institute of Electrical andElectronics Engineers (IEEE) standard 1394 bus, also called “Firewire”.

The memory 1110 and storage devices 1120 are computer-readable storagemedia that may store instructions that implement at least portions ofthe various embodiments. In addition, the data structures and messagestructures may be stored or transmitted via a data transmission medium,e.g., a signal on a communications link. Various communications linksmay be used, e.g., the Internet, a local area network, a wide areanetwork, or a point-to-point dial-up connection. Thus, computer readablemedia can include computer-readable storage media (e.g., “nontransitory” media) and computer-readable transmission media.

The instructions stored in memory 1110 can be implemented as softwareand/or firmware to program the processor(s) 1105 to carry out actionsdescribed above. In some embodiments, such software or firmware may beinitially provided to the processing system 1100 by downloading it froma remote system through the computing system 1100 (e.g., via networkadapter 1130).

The various embodiments introduced herein can be implemented by, forexample, programmable circuitry (e.g., one or more microprocessors)programmed with software and/or firmware, or entirely in special-purposehardwired (non-programmable) circuitry, or in a combination of suchforms. Special-purpose hardwired circuitry may be in the form of, forexample, one or more ASICs, PLDs, FPGAs, etc.

Remarks

The above description and drawings are illustrative and are not to beconstrued as limiting. Numerous specific details are described toprovide a thorough understanding of the disclosure. However, in certaininstances, well-known details are not described in order to avoidobscuring the description. Further, various modifications may be madewithout deviating from the scope of the embodiments. Accordingly, theembodiments are not limited except as by the appended claims.

Reference in this specification to “one embodiment” or “an embodiment”means that a particular feature, structure, or characteristic describedin connection with the embodiment is included in at least one embodimentof the disclosure. The appearances of the phrase “in one embodiment” invarious places in the specification are not necessarily all referring tothe same embodiment, nor are separate or alternative embodimentsmutually exclusive of other embodiments. Moreover, various features aredescribed which may be exhibited by some embodiments and not by others.Similarly, various requirements are described which may be requirementsfor some embodiments but not for other embodiments.

The terms used in this specification generally have their ordinarymeanings in the art, within the context of the disclosure, and in thespecific context where each term is used. Certain terms that are used todescribe the disclosure are discussed below, or elsewhere in thespecification, to provide additional guidance to the practitionerregarding the description of the disclosure. For convenience, certainterms may be highlighted, for example using italics and/or quotationmarks. The use of highlighting has no influence on the scope and meaningof a term; the scope and meaning of a term is the same, in the samecontext, whether or not it is highlighted. It will be appreciated thatthe same thing can be said in more than one way. One will recognize that“memory” is one form of a “storage” and that the terms may on occasionbe used interchangeably.

Consequently, alternative language and synonyms may be used for any oneor more of the terms discussed herein, nor is any special significanceto be placed upon whether or not a term is elaborated or discussedherein. Synonyms for certain terms are provided. A recital of one ormore synonyms does not exclude the use of other synonyms. The use ofexamples anywhere in this specification including examples of any termdiscussed herein is illustrative only, and is not intended to furtherlimit the scope and meaning of the disclosure or of any exemplifiedterm. Likewise, the disclosure is not limited to various embodimentsgiven in this specification.

Without intent to further limit the scope of the disclosure, examples ofinstruments, apparatus, methods and their related results according tothe embodiments of the present disclosure are given above. Note thattitles or subtitles may be used in the examples for convenience of areader, which in no way should limit the scope of the disclosure. Unlessotherwise defined, all technical and scientific terms used herein havethe same meaning as commonly understood by one of ordinary skill in theart to which this disclosure pertains. In the case of conflict, thepresent document, including definitions will control.

1-32. (canceled)
 33. A computer-implemented method for improving Cableand Wi-Fi coexistence in a network, comprising: determining one or moreactive Cable operations at a device; determining a plurality of one ormore harmonics corresponding to each of the active Cable operations atthe device; for at least one harmonic of the plurality of one or moreharmonics: determining a first measurement of channel quality in a firstwireless band; detecting the presence of interference in a firstwireless band, the interference caused by the at least one harmonic; andin response to the detection of the presence of interference: reducing abackoff interval; or increasing a transmission power level.
 34. Thecomputer-implemented method of claim 33, wherein the detecting thepresence of the interference in the first wireless band includes any of:determining a duration of the interference in the first wireless band;determining an interference power level of the interference in the firstwireless band; or determining that the interference power level exceedsa threshold.
 35. The computer-implemented method of claim 34, whereinthe reducing the backoff interval is based on any of the duration of theinterference, the interference power level of the interference, or thedetermination that interference power level exceeds the threshold. 36.The computer-implemented method of claim 34, wherein the increasing thetransmission power level is based on any of the duration of theinterference, the interference power level of the interference, or thedetermination that interference power level exceeds the threshold. 37.The computer-implemented method of claim 33, wherein the method furthercomprises: determining a second measurement of channel quality in thefirst wireless band following the reducing the backoff interval orfollowing the increasing the transmission power level; and effecting achannel transition from the first wireless band to a second wirelessband based on the second measurement of channel quality.
 38. Thecomputer-implemented method of claim 37, wherein the second wirelessband comprises frequencies substantially between 5.725 MHz and 5.875MHz.
 39. The computer-implemented method of claim 33, wherein thedetermining the plurality of the one or more harmonics comprisesdetermining that the Cable operation is an HRC operation associated withcausing a fourth harmonic below 2.5 GHz and consequently assessingwireless bands corresponding to at least one of wireless channels 8-14.40. The computer-implemented method of claim 33, wherein the firstwireless band comprises frequencies substantially between 2400 MHz and2500 MHz.
 41. The computer-implemented method of claim 33, wherein thebackoff is an EDCA backoff.
 42. A non-transitory computer-readablemedium comprising instructions configured to cause at least oneprocessor to perform a method comprising: determining one or more activeCable operations at a device; determining a plurality of one or moreharmonics corresponding to each of the active Cable operations at thedevice; for at least one harmonic of the plurality of one or moreharmonics: determining a first measurement of channel quality in a firstwireless band; detecting the presence of interference in a firstwireless band, the interference caused by the at least one harmonic; andin response to the detection of the presence of interference: reducing abackoff interval; or increasing a transmission power level.
 43. Acomputer system comprising: at least one processor; and at least onememory comprising instructions configured to cause the at least oneprocessor to perform a method comprising: determining one or more activeCable operations at a device; determining a plurality of one or moreharmonics corresponding to each of the active Cable operations at thedevice; for at least one harmonic of the plurality of one or moreharmonics: determining a first measurement of channel quality in a firstwireless band; detecting the presence of interference in a firstwireless band, the interference caused by the at least one harmonic; andin response to the detection of the presence of interference: reducing abackoff interval; or increasing a transmission power level.
 44. Thecomputer system of claim 43, wherein the first wireless band comprisesfrequencies substantially between 2400 MHz and 2500 MHz.
 45. Thecomputer system of claim 43, wherein the determining the plurality ofone or more harmonics comprises determining that the Cable operation isan HRC operation associated with causing a fourth harmonic below 2.5 GHzand consequently assessing wireless bands corresponding to at least oneof wireless channels 8-14.
 46. The computer system of claim 43, whereinthe backoff is an EDCA backoff.
 47. The computer system of claim 43,wherein the detecting the presence of the interference in the firstwireless band includes any of: determining a duration of theinterference in the first wireless band; determining an interferencepower level of the interference in the first wireless band; ordetermining that the interference power level exceeds a threshold. 48.The computer system of claim 47, wherein the reducing the backoffinterval is based on any of the duration of the interference, theinterference power level of the interference, or the determination thatinterference power level exceeds the threshold.
 49. The computer systemof claim 48, wherein the increasing the transmission power level isbased on any of the duration of the interference, the interference powerlevel of the interference, or the determination that interference powerlevel exceeds the threshold.
 50. The computer system of claim 43,wherein the method further comprises: determining a second measurementof channel quality in the first wireless band following the reducing thebackoff interval or following the increasing the transmission powerlevel; and effecting a channel transition from the first wireless bandto a second wireless band based on the second measurement of channelquality.
 51. The computer system of claim 50, wherein the secondwireless band comprises frequencies substantially between 5.725 MHz and5.875 MHz.
 52. The computer system of claim 43, wherein the determiningthe plurality of the one or more harmonics comprises determining thatthe Cable operation is an HRC operation associated with causing a fourthharmonic below 2.5 GHz and consequently assessing wireless bandscorresponding to at least one of wireless channels 8-14.
 53. Thecomputer system of claim 43, further comprising: when a wireless LANaccess point and Cable modem are integrated into the same device, awireless connection module querying the Cable modem directly todetermine the Cable channels that the Cable modem uses for uplink anddownlink; and said wireless connection module taking actions to avoidpotential harmonics or to mitigate the effect of the harmonics from thedownlink or uplink Cable signal.
 54. The computer system of claim 43,further comprising: when a wireless LAN access point and Cable modem aretwo separate units, a wireless connection module automaticallyanticipating harmonic interference.
 55. The computer system of claim 43,further comprising: a connection between a Cable modem and a wirelessLAN access point signaling Cable activity using said connection; andsaid wireless LAN access point or a router querying a channel of theCable modem and using information obtained by said query for channelselection.
 56. The computer system of claim 43, further comprising:during a detection period, determining whether energy levelsattributable to a Cable operation harmonic exceed a given threshold in awireless channel, wherein said threshold comprises any of time andenergy, to determine if the interference is a consistent phenomenon,wherein transitory interference does not result in a decision to avoid achannel associated with the harmonic.
 57. The computer system of claim56, further comprising: using counters from a wireless LAN physicallayer and MAC layer to measure the severity and influence ofinterference; and determining that there is excessive interference whena wireless LAN PHY module misdetects a packet preamble on interferencemore than a predetermined number of times per second.
 58. The computersystem of claim 57, further comprising: indicating that there isinterference from the wireless LAN when the MAC layer counter shows thata medium is busy more than a predetermined percent of the time that thewireless LAN is not transmitting or receiving WLAN packets; whereinduration of the time when there is non-wireless LAN interference whichresults in backing off is used as a measure of the severity ofinterference.
 59. The computer system of claim 43, further comprising:effecting a transition of a client from a first component on a wirelessdevice to a second component on the wireless device in responseinterference to establish communications via a component on the wirelessdevice that has least negative affect on the client in view of saidinterference.
 60. The computer system of claim 43, further comprising:exchanging packets between an access point and a client; wherein saidaccess point asks said client if the client can switch channels; whereinsaid client takes into account ongoing traffic when responding to saidaccess point if a switch at this time is acceptable for the client; andwherein said access point takes client feedback into account in making adecision to move the client from a first component on a wireless deviceto a second component on the wireless device.
 61. The computer system ofclaim 43, further comprising: using an extended channel switchannouncement element and/or extended channel switch announcement in abeacon and other frames to cover switches between two different bands.62. The computer system of claim 43, further comprising: a channelswitch announcement frame using an action frame for switching betweendifferent bands.
 63. The computer system of claim 43, furthercomprising: an access point deciding to move a client from one band toanother band when the access point recognizes that queues are buildingup for a client, or sees that a delay requirement is not being satisfiedfor a client.
 64. The computer system of claim 43, further comprising:an access point performing deep packet inspection to determine a type oftraffic; wherein, based on the deep packet inspection results for eachclient packet, the access point deciding which client to keep on eachband and which client to move.
 65. The computer system of claim 43,further comprising: when all receiver and transmitter mitigation failsto bring up link quality for any access point associated clients, theaccess point changing a channel of a radio which has a coexistenceissue; upon changing said channel, said access point taking into accountcoexistence when picking new channels; and said access point askingother clients for feedback on interference on all channels on the bandsupon which the radio operated before the access point issues the channelswitch; wherein interference feedback is used in addition to otherstatistics that the access point collects to pick the best channel. 66.The computer system of claim 43, further comprising: within an accesspoint having two radios in the 5 GHz band and at least on radio in the2.4 GHz band, moving a client from one radio in the 5 GHz band toanother radio in the 5 GHz band or moving a client between one radio inthe 2.4 G band and the radios in the 5 G band to provide the mosteffective channels, while taking coexistence into account.